When I ask patients with cavity problems to guess the origin of their problem, I occasionally get answers like these:
“It was some medicine I took as a child.”
“My teeth were fine until I had my children. They sucked all the calcium out of my teeth when I was pregnant. Then my teeth got weak and decayed.”
“My parents had dentures. I guess I inherited bad teeth.”
“It must be from not brushing my teeth right.”
Let us look together and see how decay really gets started, then go on to investigate how we may prevent it!
What is decay?
Teeth are made of minerals, and are the hardest organs of the body- much harder than bone! Decay is a process whereby the hard enamel outside of a tooth is dissolved by acid. Once decay gets through the enamel, the same acid dissolution progresses very quickly in the inner dentin of the tooth. If the patient does not get the cavity filled, decay invade the tooth root (containing nerves) and a toothache results.
So where does this acid come from?
It can come from a couple of sources. The most common is from bacteria living inside our mouths. Many of these sugars utilize for energy, and produce lactic acid as a by-product. It is primarily this acid which acts to dissolve teeth. Bacteria can turn dietary sugars into lactic acid in only 20 minutes. Unless the mouth is rinsed or cleaned, this acid hangs around to dissolve teeth for a whole hour! So you can see that a child who ingests candy most of the day will have an acid mouth all day, an inevitably have move than a few cavities! An adult who sips sweetened coffee most of the workday will likely suffer from the same fate.
But adults frequently get acid more directly- by drinking soda pop! Few people realize what strong acids carbonated beverages really are! Carbonated drinks are such potent acids that they can dissolve teeth directly whether the soda is “diet” or has sugar in it. I would estimate that 75% of adult decay I see is the direct result of excessive soda drinking. And as if that were not enough, too many sodas can contribute to stomach ulcers and even osteoporosis.
Other sources of acid we sometimes encounter:
Chronic vomiting, as seen in bulimia and some other disorders, can erode teeth and also cause cavities.
We have noted lately many cases of gastric reflux, where small quantities of stomach acid enter the mouth. This causes rampant destruction in your mouth, and should be controlled by prescriptions or surgery!
Don’t some medical conditions expedite decay?
Yes. Although not directly a cause of decay, any condition which dries the mouth can make your teeth more susceptible to it. Examples are doses of radiation to the head, using certain antidepressants, and antihistamines. We find that people that are mouth breathers are prone to more decay than those who can breathe normally through their nose.
Fluoride- our two-edged sword in fighting decay:
Even should physicians be unable to treat the above medical conditions, we still are able to stop decay- provided we have patient cooperation and fluoride.
Fluoride actually works two ways. It has a toxic effect on decay causing bacteria. It also hardens tooth enamel and makes it more resistant to acid attack. Interestingly, fluoride strengthens bone in the same way it strengthens teeth. Physicians sometimes use fluoride supplement to treat osteoporosis.
For adults with decay problems, we often prescribe a fluoride gel to brush on the teeth at night just before bed, and a fluoride mouth rinse in the morning. For really tough cases, including patients who have uncontrolled gastric reflux, we make custom trays to wear with fluoride at night. With this heavy-duty preventive treatment, few patients get cavities!
Kim Henry, D.M.D.